Many methods of inserting mercury into a fluorescent lamp are known, such as use of a dispensing system or incorporation into the lamp of an amalgam which is subsequently caused to release its mercury. These methods, and their disadvantages, are discussed in U.S. Pat. No. 4,182,971.
U.S. Pat. Nos. 2,288,253; 2,415,895; 3,300,037; 3,764,842; 3,794,402; 3,895,709; 3,913,999 and 3,983,439 relate to a third method wherein mercury containing capsules are mounted within a lamp to be subsequently ruptured to release the mercury. These examples require either special heaters proximate the capsule or provide loose particles within the lamp or dislodge the phosphor coating upon rupture or do not lend themselves to high speed machine production.